Sort direction (asc, desc) in Rest API - Step-by-Step Execution

Concept Flow - Sort direction (asc, desc)

Receive API request with sort param

↓

Check if sort param is 'desc'

↓

Sort data descending

↓

Return sorted data in response

↓

END

The API receives a request with a sort direction parameter, checks if it is ascending or descending, sorts the data accordingly, and returns the sorted data.

Execution Sample

Rest API

GET /items?sort=asc
// Server sorts items ascending
// Returns sorted list

This API call sorts items in ascending order and returns them.

Execution Table

Step	Input sort param	Condition	Sort Direction	Action	Output
1	asc	sort == 'desc'?	No	Sort ascending	[1, 2, 3, 4, 5]
2	desc	sort == 'desc'?	Yes	Sort descending	[5, 4, 3, 2, 1]
3	none	sort == 'desc'?	No	Default sort ascending	[1, 2, 3, 4, 5]

💡 Sorting completes and sorted data is returned in response

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3
sort_param	null	asc	desc	none
sorted_data	[]	[1, 2, 3, 4, 5]	[5, 4, 3, 2, 1]	[1, 2, 3, 4, 5]

Key Moments - 2 Insights

What happens if the sort parameter is missing or invalid?

The code defaults to ascending sort as shown in step 3 of the execution_table.

Why do we check if sort == 'desc' first?

Because if it's 'desc', we sort descending; otherwise, we sort ascending or default, as shown in steps 1 and 3.

Visual Quiz - 3 Questions

Look at the execution_table, what is the sorted_data output when sort_param is 'desc'?

A [5, 4, 3, 2, 1]

B [1, 2, 3, 4, 5]

C []

D Error

💡 Hint

Check row 2 under Output column in execution_table

At which step does the code default to ascending sort?

A Step 1

B Step 2

C Step 3

D No default

💡 Hint

Look at the Condition and Action columns in execution_table row 3

If the input sort_param changes from 'asc' to 'none', how does sorted_data change?

A From descending to ascending

B From ascending to ascending

C From ascending to descending

D No change

💡 Hint

Compare sorted_data values in variable_tracker for After Step 1 and After Step 3

Concept Snapshot

Sort direction controls order of data returned by API.
Use 'asc' for ascending, 'desc' for descending.
If missing or invalid, default to ascending.
Check sort param, then sort data accordingly.
Return sorted data in API response.

Full Transcript

This visual execution shows how a REST API handles a sort direction parameter. The API receives a request with a sort parameter that can be 'asc' or 'desc'. It checks the parameter: if it is 'asc', it sorts data in ascending order; if 'desc', it sorts descending. If the parameter is missing or invalid, it defaults to ascending sort. The sorted data is then returned in the response. The execution table traces three cases: 'asc', 'desc', and missing parameter. The variable tracker shows how the sort_param and sorted_data variables change. Key moments clarify default behavior and condition checks. The quiz tests understanding of outputs and default sorting. This helps beginners see step-by-step how sort direction affects API data sorting.